1. Field of the Invention
The present invention relates generally to methods and apparatus for splitting wood, and more particularly to method and apparatus for alternately mechanically powering a movable trolley to force a splitting wedge into a section of log with great mechanical advantage and retracting said trolley quickly with a differing substantially less mechanical advantage in preparation for reloading and recycling.
2. Description of the Prior Art
The need for power assisted log splitting equipment has long been realized, and the configuration which urges a log against a wedge has been established as the design most consistent with ease of loading and unloading operations. Numerous suggestions have been made as to how best to apply force to a wedge shaped blade so as to cause the blade to penetrate the end grain of sawn logs and cause the logs to split.
U.S. Letters Pat. Nos. 3,077,214 and 3,242,955 disclose means by which a splitting wedge or blade may be forced into a horizontally positioned log by hydraulic pressure generated by a pump and applied through a piston and cylinder arrangement. Although these designs provide both the power and control necessary to split logs, inclusion of a hydraulic system in the designs make the devices somewhat complex and relatively expensive to manufacture in that somewhat larger power sources are required because of hydraulic losses.
Several mechanically actuated non-hydraulic wood splitting machines have been proposed. U.S. Letters Pat. No. 946,705, for instance, discloses means by which a pitman is driven in reciprocating motion by rotating gears and alternately supplies splitting and retracting motion to a blade. In this machine, length of the splitting stroke and total cycle time are, of course, predetermined by the speed of rotation of the gear wheels and the manner in which the pitman is attached, so that the mechanism lacks a measure of flexibility in operation. U.S. Letters Pat. No. 1,189,999 discloses a device employing a worm and screw arrangement to supply driving force to a blade or wedge. The machine includes means by which the blade may be retracted from the work at a speed higher than that employed during the splitting stroke, thus reducing the total cycling time of the apparatus.
Devices depending on drum wound cable systems to supply longitudinal movement to blades or wedges have also been described. U.S. Letters Pat. No. 2,446,585 discloses an arrangement in which a movable table carrying a splitting head is actuated in either direction by a single strand of cable wrapped about a rotating drum, but the apparatus includes neither force multiplying sheaves nor means by which the return stroke may occur at a higher speed than the splitting stroke. U.S. Letters Pat. No. 1,310,660 describes a machine incorporating variable mechanical advantage in the splitting and return strokes but the concept is otherwise quite different from the present invention.